Water Dissolvable Released Material Used as Inflow Control Device

ABSTRACT

Methods and devices for controlling fluid flow into a wellbore tubular includes an in-flow control device, an element co-acting with the in-flow control device, and a disintegrating medium at least partially surrounding the element. The medium may be configured to release the element upon disintegration of the medium. The disintegrating medium may be configured to disintegrate when exposed to a selected fluid. The element may be configured to at least partially restrict flow across a flow path associated with the in-flow control device when released. The flow path may convey the fluid from the formation to a flow bore of the wellbore tubular and the element may be positioned along the flow path. The element may be: a liquid, a solid, a particle and/or particles. The selected fluid may be water, a hydrocarbon, an engineered fluid, and/or a naturally occurring fluid.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates generally to systems and methods for selective control of fluid flow into a wellbore.

2. Description of the Related Art

Hydrocarbons such as oil and gas are recovered from a subterranean formation using a wellbore drilled into the formation. Such wells are typically completed by placing a casing along the wellbore length and perforating the casing adjacent each such production zone to extract the formation fluids (such as hydrocarbons) into the wellbore. These production zones are sometimes separated from each other by installing a packer between the production zones. Fluid from each production zone entering the wellbore is drawn into a tubing that runs to the surface. It is desirable to have substantially even drainage along the production zone. Uneven drainage may result in undesirable conditions such as an invasive gas cone or water cone. In the instance of an oil-producing well, for example, a gas cone may cause an inflow of gas into the wellbore that could significantly reduce oil production. In like fashion, a water cone may cause an inflow of water into the oil production flow that reduces the amount and quality of the produced oil. Accordingly, it is desired to provide even drainage across a production zone and/or the ability to selectively close off or reduce inflow within production zones experiencing an undesirable influx of water and/or gas.

The present disclosure addresses these and other needs of the prior art.

SUMMARY OF THE DISCLOSURE

In aspects, the present disclosure provides an apparatus for controlling flow of a fluid into a wellbore tubular. The apparatus may include an in-flow control device controlling the flow of the fluid, an element co-acting with the in-flow control device, and a disintegrating medium at least partially surrounding the element. In arrangements, the medium may be configured to release the element upon disintegration of the medium. The disintegrating medium may be configured to disintegrate when exposed to a selected fluid. The element or elements, when released, may at least partially restrict flow across a flow path that conveys the fluid from the formation to a flow bore of the wellbore tubular. The element may be positioned along the flow path or elsewhere. In embodiments, the element may be: a liquid, a solid, a particle and/or particles. In embodiments, the selected fluid may be water, a hydrocarbon, an engineered fluid, and/or a naturally occurring fluid.

In aspects, the present disclosure provides a method for controlling a flow of fluid from a subterranean formation. In embodiments, the method may include suspending an element in a medium that disintegrates when exposed to a selected fluid; positioning the element in a wellbore; and restricting a fluid flow across a flow path by releasing the element. The method may include releasing the element into the flow path when the medium disintegrates.

In aspects, the present disclosure provides a system for controlling flow of a fluid in a well. The system may include a wellbore tubular positioned in the well; an in-flow control device positioned along the wellbore tubular; an element co-acting with the in-flow control device; and a disintegrating medium at least partially surrounding the element, the disintegrating medium being calibrated to disintegrate when exposed to a selected fluid.

It should be understood that examples of the more important features of the disclosure have been summarized rather broadly in order that detailed description thereof that follows may be better understood, and in order that the contributions to the art may be appreciated. There are, of course, additional features of the disclosure that will be described hereinafter and which will form the subject of the claims appended hereto.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages and further aspects of the disclosure will be readily appreciated by those of ordinary skill in the art as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference characters designate like or similar elements throughout the several figures of the drawing and wherein:

FIG. 1 is a schematic elevation view of an exemplary multi-zonal wellbore and production assembly which incorporates an inflow control system in accordance with one embodiment of the present disclosure;

FIG. 2 is a schematic elevation view of an exemplary open hole production assembly which incorporates an inflow control system in accordance with one embodiment of the present disclosure;

FIG. 3 is a schematic cross-sectional view of an exemplary production control device made in accordance with one embodiment of the present disclosure;

FIGS. 4A-4B schematically illustrate a material suspended in a medium in accordance with one embodiment of the present disclosure that may be released to actuate a flow restriction element;

FIGS. 5A-5B schematically illustrate a material suspended in a medium that is made in accordance with one embodiment of the present disclosure that may be released to restrict fluid flow; and

FIGS. 6A-6B schematically illustrate occlusion elements suspended in a medium that is made in accordance with one embodiment of the present disclosure that may be released to restrict fluid flow.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present disclosure relates to devices and methods for controlling production of a hydrocarbon producing well. The present disclosure is susceptible to embodiments of different forms. There are shown in the drawings, and herein will be described in detail, specific embodiments of the present disclosure with the understanding that the present disclosure is to be considered an exemplification of the principles of the disclosure, and is not intended to limit the disclosure to that illustrated and described herein. Further, while embodiments may be described as having one or more features or a combination of two or more features, such a feature or a combination of features should not be construed as essential unless expressly stated as essential.

Referring initially to FIG. 1, there is shown an exemplary wellbore 10 that has been drilled through the earth 12 and into a pair of formations 14, 16 from which it is desired to produce hydrocarbons. The wellbore 10 is cased by metal casing, as is known in the art, and a number of perforations 18 penetrate and extend into the formations 14, 16 so that production fluids may flow from the formations 14, 16 into the wellbore 10. The wellbore 10 has a deviated, or substantially horizontal leg 19. The wellbore 10 has a late-stage production assembly, generally indicated at 20, disposed therein by a tubing string 22 that extends downwardly from a wellhead 24 at the surface 26 of the wellbore 10. The production assembly 20 defines an internal axial flowbore 28 along its length. An annulus 30 is defined between the production assembly 20 and the wellbore casing. The production assembly 20 has a deviated, generally horizontal portion 32 that extends along the deviated leg 19 of the wellbore 10. Production devices 34 are positioned at selected points along the production assembly 20. Optionally, each production device 34 is isolated within the wellbore 10 by a pair of packer devices 36. Although only two production devices 34 are shown in FIG. 1, there may, in fact, be a large number of such production devices arranged in serial fashion along the horizontal portion 32.

Each production device 34 features a production control device 38 that is used to govern one or more aspects of a flow of one or more fluids into the production assembly 20. As used herein, the term “fluid” or “fluids” includes liquids, gases, hydrocarbons, multi-phase fluids, mixtures of two of more fluids, water, brine, engineered fluids such as drilling mud, fluids injected from the surface such as water, and naturally occurring fluids such as oil and gas. Additionally, references to water should be construed to also include water-based fluids; e.g., brine or salt water. In accordance with embodiments of the present disclosure, the production control device 38 may have a number of alternative constructions that ensure selective operation and controlled fluid flow therethrough.

FIG. 2 illustrates an exemplary open hole wellbore arrangement 11 wherein the production devices of the present disclosure may be used. Construction and operation of the open hole wellbore 11 is similar in most respects to the wellbore 10 described previously. However, the wellbore arrangement 11 has an uncased borehole that is directly open to the formations 14, 16. Production fluids, therefore, flow directly from the formations 14, 16, and into the annulus 30 that is defined between the production assembly 21 and the wall of the wellbore 11. There are no perforations, and open hole packers 36 may be used to isolate the production control devices 38. The nature of the production control device is such that the fluid flow is directed from the formation 16 directly to the nearest production device 34, hence resulting in a balanced flow. In some instances, packers maybe omitted from the open hole completion.

Referring now to FIG. 3, there is shown one embodiment of a production control device 100 for controlling the flow of fluids from a reservoir into a production string via one or more passages 122. This flow control can be a function of one or more characteristics or parameters of the formation fluid, including water content, fluid velocity, gas content, etc. Furthermore, the control devices 100 can be distributed along a section of a production well to provide fluid control at multiple locations. This can be advantageous, for example, to equalize production flow of oil in situations wherein a greater flow rate is expected at a “heel” of a horizontal well than at the “toe” of the horizontal well. By appropriately configuring the production control devices 100, such as by pressure equalization or by restricting inflow of gas or water, a well owner can increase the likelihood that an oil bearing reservoir will drain efficiently. Exemplary production control devices are discussed herein below.

In one embodiment, the production control device 100 includes a particulate control device 110 for reducing the amount and size of particulates entrained in the fluids, a flow control device 120 that controls overall drainage rate from the formation, and an in-flow control device 130 that controls in-flow area based upon the composition of a fluid in the vicinity of the in-flow control device 130. The particulate control device 110 can include known devices such as sand screens and associated gravel packs and the flow control device 120 can utilize devices employing tortuous fluid paths designed to control inflow rate by created pressure drops.

An exemplary in-flow control device 130 may be configured to control fluid flow into a flow bore 102 based upon one or more characteristics (e.g., water content) of the in-flowing fluid. In embodiments, the in-flow control device 130 is actuated by one or more element 132 that is partially or completed suspended in a medium 134 that disintegrates upon exposure to one or more specified fluids in the vicinity of the in-flow control device 130. The elements 132 may, depending on the application, be a solid, a liquid, a slurry, a particle, particles or an engineered component. The medium 134 is a body of one or more materials that have a relatively fast rate of disintegration. Exemplary types of disintegration include, but are not limited to, oxidizing, dissolving, melting, fracturing, and other such mechanisms that cause a structure to lose integrity and fail or collapse. The medium 134 may be formed of a material, such as aluminum, that oxidizes, or corrodes, when exposed to water. In embodiments, the elements 132 may be calibrated to disintegrate. By calibrate or calibrated, it is meant that one or more characteristics relating to the capacity of the element to disintegrate is intentionally tune or adjusted to occur in a predetermined manner or in response to a predetermined condition or set of conditions. For convenience, the “elements” as used herein are not intended to limit the present disclosure as requiring a plurality of discrete elements. Rather, the term “elements” is used merely for the sake of convenience. Embodiments of the present disclosure may utilize one or more “elements” as described herein.

As will be appreciated, the elements 132 suspended in the medium 134 may be used in numerous arrangements to partially or complete restrict flow through the in-flow control device 130. In embodiments, the medium 134 may dissolve or otherwise disintegrate when a threshold value of water concentration, or water cut, in the fluid flowing across the in-flow control device 130 exceeds a preset value. Once the disintegration sufficiently degrades the medium 134, the elements 132 are released to perform any number of functions. Illustrative functions for the elements 132 are described below.

Referring now to FIGS. 4A-B, there is schematically shown an in-flow control device 150 that restricts fluid flow into a flow bore 102 when the amount of water in the fluid exceeds a predetermined value. The in-flow control device 150 may include a housing 152 and a flow restriction element 154 that is positioned on a wellbore “low side.” The flow restriction element 154 may move between an open position (FIG. 4A) and a closed position (FIG. 4B). In the open position as shown, fluid flows from an annular passage 103 into the flow bore 102. In the closed position, the flow restriction element 154 partially or completely blocks the passages (not shown) to thereby restrict flow into the flow bore 102. The flow restriction element 154 may be formed to have an overall density greater than that of oil and of water. Thus, the flow restriction element 154 “sinks” to the open position due to gravity when immersed in either water or oil. The flow restriction element 154 may rotate, as shown, between the open and closed positions but may also utilize other modes of movement, e.g., translation. To move the flow restriction element 154 to a closed position, a relatively dense material 160 may be suspended in a medium 162 that disintegrates when exposed to a predetermined amount of water in a fluid in the in-flow control device 150. The relatively dense material 160 may be positioned in the housing 152 or elsewhere upstream of the flow restriction element 154. In one arrangement, the relatively dense material 160 may be a fluid or slurry that has a density greater than the overall density of the flow restriction element 154.

Referring now to FIG. 4B, in an illustrative deployment, the fluid flowing through the in-flow control device 150 may initially not have sufficient water content to degrade the medium 162. For instance, the fluid flowing through the in-flow control device 150 may be mostly oil. Because the overall density of the flow restriction element 154 is greater than that of oil, the flow restriction element 154 “sinks” to an open position to allow the fluid to enter the flow bore 102. Moreover, the relatively dense material 160 remains suspended in the medium 162. If the in-flow control device 150 encounters an increase in water concentration in the flowing fluid sufficient to disintegrate the medium 162, then the relatively dense material 152 will be released into the housing 152 and collect around the flow restriction element 154. As noted above, the effective density of the flow restriction element 154 is less than the density of the relatively dense material 160. Thus, as the relatively dense material 152 collects around the flow restriction element 154, the flow restriction element 154 will “float” to the closed position and fluid flow into the flow bore 102 will be restricted.

Referring now to FIGS. 5A-B, there is schematically shown an in-flow control device 170 that selectively restricts fluid flow along a flow path 172 when the amount of water in the fluid exceeds a predetermined value. The in-flow control device 170 may include a housing 174 and a permeable element 176 that is positioned along the flow path 172. The permeable element 176 includes openings and/or passages (not shown) that do not substantially restrict the flow of fluid along the flow path 172. In embodiments, the permeable element 176 may be a filter-type element, a membrane, or a screen. As shown by the arrows 178, fluid passes through the permeable element 176 with little obstruction. To restrict flow in the flow path 172, a quantity of particles 180 may be entrained in a medium 182 that disintegrates when exposed to a predetermined amount of water in a fluid in the in-flow control device 170. The particles 180 may be positioned in the housing 174 or elsewhere upstream of the permeable element 176. In embodiments, the particles 180 may be a proppant, a powder, particulates, granular matter, pellets or other material having a shape or size that prevents the material from passing through the openings and/or passages of the permeable element 176. Suitable materials for the particles include, but are not limited to, metals, plastics, composites, ceramics, polymers, gels, etc.

Referring now to FIG. 5B, in an illustrative deployment, the fluid flowing through the in-flow control device 170 may initially not have sufficient water content to degrade the medium 182. For instance, the fluid flowing through the in-flow control device 170 may be mostly oil. Thus, the oil flows substantially freely through the permeable element 176. Moreover, the particles 180 remain suspended in the medium 182. If the in-flow control device 170 encounters an increase in water concentration in the flowing fluid sufficient to disintegrate the medium 182, then the particles 180 will be released into the housing 174 along the flow path 172. As noted above, the shape and/or size of the particles 180 cannot pass through the permeable element 176. Thus, the particles form a layer on the permeable element 176 that at least partially occludes the passages and/or openings in the permeable element 176. As shown by the arrows 184, less fluid passes through the permeable element 176 and through the flow path 172.

Referring now to FIGS. 6A-B, there is schematically shown an in-flow control device 190 that selectively restricts fluid flow along a flow path 192 when the amount of water in the fluid exceeds a predetermined value. The in-flow control device 190 may include a housing 194 and orifices 196 that communicate with a flow bore 102. To restrict flow into the flow bore 102, plugging members 200 may be fixed in a medium 202 that disintegrates when exposed to a predetermined amount of water in a fluid in the in-flow control device 190. The plugging members 200 may be positioned in the housing 194 or elsewhere upstream of the orifices 196. In embodiments, the plugging members 200 may balls members, pellets, granular elements other members have a shape or size that prevents the members from passing through the orifices 196. Suitable materials for the particles include, but are not limited to, metals, plastics, composites, ceramics, polymers. In embodiments, there may be numerically more orifices 196 than plugging members 200 to ensure that some amount of flow may still occur through the in-flow control device 190 even after the plugging members 200 are released; e.g., eight plugging members 200 and ten orifices 196.

Referring now to FIG. 6B, in an illustrative deployment, the fluid flowing through the in-flow control device 190 may initially not have sufficient water content to degrade the medium 192. For instance, the fluid flowing through the in-flow control device 190 may be mostly oil. Thus, the oil flows substantially freely through the orifices 196. Moreover, the plugging members 200 remain suspended in the medium 192. If the in-flow control device 190 encounters an increase in water concentration in the flowing fluid sufficient to disintegrate the medium 192, then the plugging members 200 will be released into the housing 194. As noted above, due to their shape and/or size, the plugging members 200 cannot pass through the orifices 196. Thus, a plugging member 200 occludes or substantially block fluid flow across the orifice 196 within which it is seated.

It should be understood that the above-described embodiments are merely illustrative of the arrangements wherein an element suspended in a media may be released to restrict flow from a formation into a production flow bore. For instance, in FIG. 5A, the permeable element 176 is shown positioned along a flow path upstream of orifices 122 (FIG. 3). In other embodiments, the permeable membrane 176 may be positioned in the same manner as the orifices 196 of FIGS. 6A-B; e.g., at the orifices 122. Thus, the released particles 180 may form a horizontal bed that blocks flow instead of the vertical layer shown in FIG. 5B. In other variants, the above-described elements may be positioned at other locations, such as the particulate control device 110 (FIG. 3) or the flow control device 120 (FIG. 3) or even external to the production control device 100 (FIG. 3).

Additionally, in certain embodiments, the elements suspended within the disintegrating medium may be formed of material that disintegrates when exposed to oil. Thus, for instance, an oil-soluble plugging element may be encapsulated in a water soluble media. In such an arrangement, if the flowing fluid were to return to substantially oil flow after the oil-plugging element has seated into an orifice, then the oil-soluble element may disintegrate to restore flow through that orifice. It should be appreciated that such an arrangement provides a reversible in-flow control mechanism. In other embodiments, a fluid supplied from the surface may be used to displace or disintegrate an element plugging an orifice, permeable membrane or actuating a flow restriction element.

For the sake of clarity and brevity, descriptions of most threaded connections between tubular elements, elastomeric seals, such as o-rings, and other well-understood techniques are omitted in the above description. The foregoing description is directed to particular embodiments of the present disclosure for the purpose of illustration and explanation. It will be apparent, however, to one skilled in the art that many modifications and changes to the embodiment set forth above are possible without departing from the scope of the disclosure. 

1. A method for controlling a flow of fluid from a subterranean formation, comprising: positioning a housing in a wellbore, the housing having a flow path formed therein; suspending an element in a medium that disintegrates when exposed to a selected fluid; positioning the element in housing; and restricting a fluid flow across the flow path by releasing the element.
 2. The method according to claim 1 wherein the selected fluid is water.
 3. The method according to claim 1 further comprising releasing the element into the flow path when the medium disintegrates.
 4. The method according to claim 1 further comprising configuring the flow path to convey fluid from the formation into a bore of a wellbore tubular; forming a passage in the housing and that communicates with the bore of the wellbore tubular; and at least partially blocking the passage with the element by releasing the element.
 5. The method according to claim 1 further comprising forming the flow path to convey the fluid from the formation to a flow bore of a wellbore tubular; and reducing an amount of particles in the fluid entering the flow path by using a particulate control device.
 6. The method according to claim 1 further comprising positioning the element along the flow path and maintaining the element substantially stationary in the flow path while the element is suspended in the medium.
 7. The method according to claim 1 wherein the element is one of: (i) a liquid, (ii) a solid, (iii) a particle, and (iv) particles.
 8. The method according to claim 1 wherein the selected fluid is one of: (i) water, (ii) a hydrocarbon, (iii) an engineered fluid, and (iv) a naturally occurring fluid.
 9. An apparatus for controlling flow of a fluid into a wellbore tubular, comprising: an in-flow control device having a housing; an element positioned in the housing; and a disintegrating medium at least partially surrounding the element, the disintegrating medium being configured to disintegrate when exposed to a selected fluid.
 10. The apparatus according to claim 9 wherein the disintegrating medium disintegrates upon exposure to water in the fluid.
 11. The apparatus according to claim 9 wherein the element is configured to at least partially restrict flow across a flow path associated with the in-flow control device.
 12. The apparatus according to claim 9 wherein the medium is configured to release the element after the medium at least partially disintegrates.
 13. The apparatus according to claim 9 further comprising a flow path to convey the fluid from the formation to a flow bore of the wellbore tubular.
 14. The apparatus according to claim 13 wherein the element is positioned along the flow path.
 15. The apparatus according to claim 9 wherein the element is one of: (i) a liquid, (ii) a solid, (iii) a particle, and (iv) particles.
 16. The apparatus according to claim 9 wherein the selected fluid is one of: (i) water, (ii) a hydrocarbon, (iii) an engineered fluid, and (iv) a naturally occurring fluid.
 17. A system for controlling flow of a fluid in a well, comprising: a wellbore tubular positioned in the well; an in-flow control device having a housing and positioned along the wellbore tubular; an element positioned in the housing; and a disintegrating medium at least partially surrounding the element, the disintegrating medium being calibrated to disintegrate when exposed to a selected fluid.
 18. The system according to claim 17 wherein the disintegrating medium disintegrates upon exposure to water in the fluid.
 19. The system according to claim 17 wherein the element is configured to at least partially restrict flow across a flow path associated with the in-flow control device.
 20. The system according to claim 17 wherein the medium is configured to release the element upon disintegration of the medium.
 21. A method for controlling a flow of fluid from a subterranean formation, comprising: flowing a fluid from an annulus of a wellbore into a flow bore of a wellbore tubular; reducing one of (i) a size and (ii) an amount of particles in the fluid flowing into the flow bore; suspending in a flow path of the fluid an element in a medium that disintegrates when exposed to a selected fluid; and restricting a fluid flow across the flow path by releasing the element when the flowing fluid includes the selected fluid.
 22. The method according to claim 21 further comprising: forming a passage along the flow path, the passage communicating with the flow bore of the wellbore tubular; and at least partially blocking the passage with the released element. 